Snap action switch



July 23, 1963 F. N. ANDERSON SNAP ACTION SWITCH Filed July 21, 1961INVENTOR. @250 IV. ANDERSON fins Arm/mars United States Patent Myinvention relates to a new and useful improvement in a snap actionswitch and more particularly to an electrical switch having anarrangement of parts whereby the movable contact bearing blade israpidly actuated for making and breaking electrical contacts.

A particular object of my invention is in the provision in a snap actionswitch of this character of a suspended type movable switch blade thathas no fixed connection to the switch housing.

A further object of my invention is in the provision in a snap actionswitch of this character of an arrangement of parts whereby a terminalpost pivotally supports in a suspended relation a movable switch bladewithin a switch housing and bet-ween fixed contact bearing terminalmembers.

Yet another object of my invention is in the provision in a snap actionswitch of this character of a compression spring utilized forresiliently retaining the movable switch blade in operable positionwhile simultaneously controlling the operation and positioning of amovable actuator for the switch blade.

Still another important object of my invention is in the provision in asnap action switch of this character of an arrangement of parts thatpermits the operating elements of the switch to be easily and quicklyassembled within a switch housing.

Other objects will appear hereinafter.

- The invention consists in the novel combination and arrangements ofparts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanyingdrawings showing the preferred form of construction, and in which:

FIG. 1 is a perspective view of my complete switch assembled.

FIG. 2 is an end elevational view of the same.

FIG. 3 is a side elevational view with the cover removed.

FIG. 4 is a side elevational view similar .to FIG. 3 but showing theparts in their actuated position, and

FIG. 5 is a perspective view of certain parts of my invention in anexploded relation as shown in FIG. 3.

My improved snap action switch mechanism is adapted to be housed in acavity formed in a casing 10. The cats ing is provided with a removableside cover 11 which affords ready access to the cavity formed in thecasing 10.

Extending through appropriate slots 12 and 13, comp-lementarily formedin the side wall :14 of the casing and cover 111, are fixed terminalmembers 15 and 16. These terminal members 15 and 16 on that portionthereof which is positioned within the cavity of the casing 10 areprovided with spaced apart confronting contacts 15' and 16'. Theseterminal members 15 and 16 have their inner ends which are positionedwithin the cavity of the casing 10 bent at oppositely extending rightangles and such angled ends are provided with laterally extending studs17 and 18 which are inserted into locating apertures 19 and 20 formed inthe back wall 21 and inner surface of the cover 11.

The bottom wall 22 of the casing 10 and cover 11 has formed therein aslot 23, in which a third terminal member 24 is positioned. Thisterminal member 24 is angularly formed so as to provide a pivot post 25centrally located within the cavity of the casing 10. The

pivot post 25 has formed in one side face thereof a V- notch 26, whichextends transversely to the longitudinal length of the post 25. Theopposite side face of the pivot post 25 is provided with a laterallyextending circular stud 27 as seen in FIG. 5.

Positioned Within the cavity of the casing 15 is a movable switch blade28 which comprises a unitary flat strip of spring material, slotted asat 29 and 30 so as to provide apair of outer tension bars 31 and 32. Byslotting the strip as at 29 and 30, I provide a pair of oppositelyextending fingers 33 and 34 which have their confronting free endsspaced apart as shown in FIG. 5. Each of the fingers 33 and 34 have asubstantial portion of their length angularly disposed out of the flatplane of the blade 28 into depending bisecting planes when mountedwithin the casing 10 as shown in FIG. 3.

One end of the blade 28 is provided with a contact member 35 which isnormally disposed in contact with one of the contacts 15' and :16 of thefixed terminal members 11-5 and 16. The opposite end of the blade 28together with a portion of the finger 33 provides an enlarged fiatbearing surface 36 upon which is adapted to set one end 67 of theactuator 38.

The actuator 38 is adapted to be slidably contained in a slot 39 formedin the casing 10, which slot 39 at its lower end is in opencommunication with the cavity formed in the casing .10. The one end 37of the actuator 38 is provided with a side projection 40 which preventsthe actuator 38 from moving upwardly through the slot 39 and out of thecasing .10.

In assembling the snap action switch of my invention, the fixed terminalmembers 15, 1'6, and 24, are placed in their appropriate slots 12, 13,and 23, formed in the casing 10. The switch blade is placed in thecavity of the casing 10 with the terminal post 25 positioned between thetension bars 31 and 32 and with the free end of the finger 34 seatedwithin the V-notch 26 as shown in FIGS. 3 and 4.

A compression spring 41 is seated upon the stud 27 pro vided by the post25 :and convoluted about the finger 33, with its end resting upon(laterally extending shoulders 42 provided by the enlarged bearingsurface 36. This compression spring 41 exerts a line of force throughthe angled portion of the finger 33 so :as to urge the switch blade 28to the left as viewed in FIGS. 3 and 4 in the direction of the end wall43 of the casing 10.

The compression spring 41 will yieldably bear the end of the finger 34into a seated pivotal position in the V-notch 26 of the pivot post 25.By reason of the angular position of the spring 41 the switch blade 28will also be forced upwardly in the direction of the angular plane ofthe finger 33. This will place the tension bars 31 and 32 under tension,and finger 34 under compression and will cause the opposite end of theblade 28, carrying the contact 35, the be positioned in contact with thecon tact 15' of the terminal member 15.

The end of the actuator 38 will sit upon the enlarged bearing surface 36of the switch blade 28. The spring 41 will be compressed upon the stud27 of the post 25 by downward movement of that end of the blade 28 thatprovides, together with finger 33, the enlarged bearing surface 36. Thismovement is accomplished through the depressing of the actuator 38inwardly of the casing 10. Such movement of the actuator 38 and one endof the blade 28 is against the action of the spring 41. As the enlargedbearing surface 36 of the blade 28' thus moves downwardly, as shown inFIGS. 3 and 4, it will cause the corresponding connected ends of thetension bars 31 and 32 to flex downwardly in the direction of thehorizontal plane of the angled portion of the finger 34.

As the actuator 38 forces the tension bars 31 and 32' to move downwardlybeneath the plane of the finger 34 and its pivotal connection to thepost 25, the contact 35 on that end of the switch blade 28 will movewith a snap action downwardly into contact with the contact 16 of thefixed terminal member 16 as viewed in FIG. 4. In such actuated position,it should be noted that the free ends of the angular portions of thefingers 33' and 34 are now disposed in substantial spaced apart planeson opposite sides of the blade 28. The direction of the force exerted bythe compression spring- 41 is still substantially in an obliquedirection with respect to the fiat plane of the blade 28 and thus in aposition to efiect rrestonation of the blade 28 into its originalcondition as seen in FIG. 3 when the moving force is removed from theactuator 38.

While I' have illustrated and described the preferred form ofconstruction for carrying my invention into effect, this is capable ofvariation and modification without departing from the spirit of theinvention. I theretore do not wish-to be limited to the precise detailsof constnuction set forth but desire to avail myself of such variationand modification as come within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire toprotect by Letters Patent is:

1. In a switch of the class described comprising (a) a substantiallyflat switch blade formed of spring material slotted'longitudinally toform a pair of paral- I with respect to the fixed contacts, a movableswitch actua lel side tension bars connected together at opposite Qends,

(12) one end of said blade having an electrical contact thereon adaptedfor movement between two spaced apart fixed contacts with the oppositeend of said blade providing an actuator seat.

(c) said blade providing between said tension bars confronting spacedapart fingers each having a' substantialportion of their lengthangular-1y disposed out of and beneath the longitudinal plane of saidtension 'bai's when said blade is mounted in said switch,

(d) a fixed terminal post member provided by said switch and havingpivotal connection with the free end of one of said fingers at a pointbelow the normal'longitudin-al plane of said blade,

(e) a coil spring disposed between said terminal post and said otherlinger for urging said blade in one direction relative to itslongitudinal length so as to place under compression said one of saidfingers and to yieldably urge said actuator seat into engagement with aswitch actuator,

(f) and a switch actuator slidably carried by said switch and having aportion thereof in contact with said seat provided by said opposite endof said switch blade,

(g) said actuator movable perpendicularly against said seat provided bysaid blade to move said tension bars thereof relative to said terminalpost member and tor freely engaging the switch blade at one end thereof,

' (a) a snap action mechanism including a pair of spaced apartconfironting fingers integrally formed from the blade andhaving asubstantial portion of their length 'langularly disposed into bisectingplanes extending downwardly of the longitudinal plane of the blade whenin assembly condition,

(1)) a fixed support extending tangentially between said fingers andhaving pivotal contact with one of said fingers at a point below thelongitudinal plane of the blade,

(c) a resilient means interposed between said support and said otherfinger for yieldably positioning the blade in its first position andsaid one end thereof in engagement with said switch actuator and foryieldably resisting movement of said switch actuator.

(d) said switch actuator movable against said resilient means for movingwith a snap-action the switch bladeinto its second position below thepoint of pivotal contact between said one of said fingers and saidsupport and into contact with the other of said fixed contacts with saidswitch blade changing its planar relation with respect to said one ofsaid fingers while the other cf said fingers maintains its angularrelation with respect thereto and to said switch actuator.

3 In a switch of'the class described and defined by claim-2 wherein-saidfixed support includes a combination terminal and pivot post, said postproviding a laterally extending stud about which sets one end of saidresilient means, said stud adapted to prevent displacement of saidresilient means trom said post when said actuator is moved againstswitchblade.

4. In a switch of the class described and defined by claim 2' whereinsaid resilient means includes a coil spring.

References Cited in the file of this patent UNITED STATES PATENTSPetensen June 3, 1930 Miller- June 3, 1952

1. IN A SWITCH OF THE CLASS DESCRIBED COMPRISING (A) A SUBSTANTIALLYFLAT SWITCH BLADE FORMED OF SPRING MATERIAL SLOTTED LONGITUDINALLY TOFORM A PAIR OF PARALLEL SIDE TENSION BARS CONNECTED TOGETHER AT OPPOSITEENDS, (B) ONE END OF SAID BLADE HAVING AN ELECTRICAL CONTACT THEREONADAPTED FOR MOVEMENT BETWEEN TWO SPACED APART FIXED CONTACTS WITH THEOPPOSITE END OF SAID BLADE PROVIDING AN ACTUATOR SEAT. (C) SAID BLADEPROVIDING BETWEEN SAID TENSION BARS CONFRONTING SPACED APART FINGERSEACH HAVING A SUBSTANTIAL PORTION OF THEIR LENGTH ANGULARLY DISPOSED OUTOF AND BENEATH THE LONGITUDINAL PLANE OF SAID TENSION BARS WHEN SAIDBLADE IS MOUNTED IN SAID SWITCH, (D) A FIXED TERMINAL POST MEMBERPROVIDED BY SAID SWITCH AND HAVING PIVOTAL CONNECTION WITH THE FREE ENDOF ONE OF SAID FINGERS AT A POINT BELOW THE NORMAL LONGITUDINAL PLANE OFSAID BLADE, (E) A COIL SPRING DISPOSED BETWEEN SAID TERMINAL POST ANDSAID OTHER FINGER FOR URGING SAID BLADE IN ONE DIRECTION RELATIVE TO ITSLONGITUDINAL LENGTH SO AS TO PLANE UNDER COMPRESSION SAID ONE OF SAIDFINGERS AND TO YIELDABLY URGE SAID ACTUATOR SEAT INTO ENGAGEMENT WITH ASWITCH ACTUATOR, (F) AND A SWITCH ACTUATOR SLIDABLY CARRIED BY SAIDSWITCH AND HAVING A PORTION THEREOF IN CONTACT WITH SAID SEAT PROVIDEDBY SAID OPPOSITE END OF SAID SWITCH BLADE, (G) SAID ACTUATOR MOVABLEPERPENDICULARLY AGAINST SAID SEAT PROVIDED BY SAID BLADE TO MOVE SAIDTENSION BARS THEREOF RELATIVE TO SAID TERMINAL POST MEMBER AND SAIDFINGERS INTO A SUBSTANTIALLY PARALLEL RELATION ON OPPOSITE SIDES OF SAIDTENSION BARS IN A SWITCH ACTUATED POSITION, (H) SAID COIL SPRINGYIELDABLY RESISTING THE PERPENDICULAR MOVEMENT OF SAID ACTUATOR WHILEMAINTAINING CONTACT PRESSURE BETWEEN SAID ELECTRICAL CONTACT ON ONE ENDOF SAID BLADE AND A FIXED CONTACT AND SAID ACTUATOR SEAT ON THE OPPOSITEEND OF SAID BLADE IN ENGAGEMENT WITH SAID ACUATOR.